In a conventional technique, machine tools are known which perform machining, such as cutting, by moving tools relative to workpieces. In such machine tools, a numerical control-type machine tool is known which specifies a path of a tool with respect to a workpiece by coordinates of a predetermined axis or the like and performs machining by moving the tool with respect to the workpiece. At least one of the workpiece and the tool is moved, so that machining, such as cutting, can be performed while changing a relative position of the tool to the workpiece.
The machine tool performs machining on a workpiece having a predetermined shape to form the workpiece into a target shape. A machining program for driving the machine tool can be generated by a user as well as a computer aided manufacturing (CAM) device based on a target shape of a designed workpiece. The target shape of the workpiece can be generated by, for example, a computer aided design (CAD) device. Data of the target shape of the workpiece generated by the CAD device is supplied to the CAM device. The CAM device can generate the machining program for the machine tool based on the target shape of the workpiece. In such a system, many processes can be automated for machining a workpiece having a desired shape.
According to Japanese Laid-open Patent Publication No. 2012-164269, a machining path producing method for removing a part of a material by cutting. The method is to automatically judge a shape which can be cracked based on a three-dimensional CAD model of a product design and automatically generate a machining path for a cracking machining method.